Electric fuse-lighter.



E. C. woon.

ELECTRLC FUSE LIGHTER. APPLlcATIoN HLEDNNE 11,* ma. RENwED Nov. a0. 1917.

1,258,075. Patented MarY 5, 1918.

f//j s UNITED STATES PATENT OFFICE.

EDWIN C. WOOD, OF DENVER, COLORADO.

ELECTRIC FUSE-LIGHTER.

Application filed .Tune 17, 1916, Serial No. 104,296.

To `all whom t 'may concern.'

Be it known that I, EDWIN C. Woon, a citizen of the United States, residing at the city and county of Denver and State of Colorado, have invented certain new and useful Improvements in Electric Fuse- Lighters; and I do declare the following to be a full, clear, and exact description of -the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the characters of reference marked thereon, which form apart of this specification.

My invention relates to improvements in fuse lighters, my object being to provide a device of this class which shall facilitate the work of lighting fuses as compared with the devices intended for thisv purpose and heretofore employed.

The invention is more especially intended for use in lighting fuses in mines where these fuses are connected with charges of powder which have been introduced into drill holes formed in the rock, these charges being securely conned by filling the holes infront of the powder charges and tightly tamping the filling in place around the fuses which are connected at one extremity with the charges of powder, while their opposite extremities extend beyond the holes in the rock for lighting purposes.

Heretofore, so far as I am aware, these fuses have been lighted after first splitting them by means of a knife of ordinary construction, until kthe powder is exposed, after which the blaze of a candle or other light is applied directly to the exposed powder in the fuses.

The diiiculty of lighting fuses in the ordinary way as just explained, is considerable, particularly, in wet mines (and most mines are wet), since, when the powder is exposed by splitting the fuse, the water which is continually dripping in wet mines, is liable to reach the powder and prevent lighting, unless great care is taken on the part of the operator. Again, it is custemary for a single person to light a number of fuses, say from twelve to twenty, the lighting being done in such a manner that some of the charges of powder will explode simultaneously and others successively, this result being brought about by lighting the fuses at various distances from the face of the rock or from the powder charges. In order to do this Specification of Letters Patent.

Patented Mar. 5, 1918.

Renewed November 30, 1917. Serial No. 204,783.

work accurately the operator must judge the time which will be required for the fire to travel through the fuse to the charge. Under the old method it is extremely diilicult to judge the time with reasonable accuracy, since, while one fuse may be readily lighted, difficulty may attend the lighting of the next fuse by reason of the powder becoming wet or because of some other difficulty. Again, it often happens that accidents occur in mines b v premature explosions by reason of the difficulty of accurately judging the time required for the fire to reach the charges. This difiiculty often results in serious injury to the person in charge of the work.

My present improvement is intended to overcome this ditliculty, since it is calculated to light every fuse, the instant it is applied thereto and the jaws of the lighter closed thereon. The device consists of two normally open pivoted jaws equipped with with fuse-piercing or splitting points or electrodes, which, when the jaws are closed, penetrate the fuse on opposite sides, whereby the points of the electrodes come into contact in the center of the fuse where the powder is located. These electrodes are connected in a proper electrical circuit, whereby the latter is closed as the points come together. Immediately after closing the jaws, the operator releases the pressure and a spring acts to immediately open them and during this opening operation, an electric arc between the points of the electrodes is established and ignites the powder in the fuse. By the use of this tool any desired number of fuses may vbe lighted within a given time, which may be judged with such accuracy as to practically overcome all of the ditliculties and dangers heretofore experienced in lighting fuses in the ordinary way.

Having brieiiy outlined my improvement, I will proceed to describe the same in detail, reference being made to the accompanying drawing, in which is illustrated an embodiment thereof. In this drawing,-

Figure 1 is an elevation of my improved fuse lighter showing the same with the jaws closed upon the fuse as is required in using the tool.

Fig. 2 shows the same device with the jaws open, the circuit with which the fusesplitting points or electrodes are connected, being also illustrated.

Fig. 3 is an end elevation of the tool when the jaws are closed, being a view looking in the direction of arrow 3, Fig. 1.

Fig. 1 is a section taken on the line e-, Fig. 1.

Fig. 5 is a detail view of one of the splitting devices or electrodes shown in connection with its electrical conductor, the conductor and the electrode being suitably embedded in insulating material except at one extremity of each.

Fig. 6 is a detail view showing the penetrating electrodes on a larger scale and in contact.

The same reference characters indicate the same parts in all the views.

Let the nume 1al 5 designate the body portion of my improved tool, which is composed of two coperating members 6 and 7 whose forward extremities 8 and 9 are preferably composed of metal and connected by a hinge pin 10. These metal parts 8 and 9 are recessed as shown at 12 and 13 to receive a spiral spring 14 which when the jaws are closed, is under tension, and whose rccoil serves to instantly open the jaws when the closing pressure is released. Located just in the rear of the extremities 8 and 9, are two insulating bloc-ks 15 and 1G in which are embedded electrodes 17 and 18 having` exposed points 19 and 20. The point 19 of the electrode 17, projects into a recess 21 formed in the insulating block and which is adapted to receive a projection 22 of the block 16. The point 2O projects beyond the projection 22, the two points 19 and 20 being therefore so arranged that when the jaws are closed they will be brought into direct contact with each other as shown in Fig. 6. It is advisable in the construction of the device, that the points should slightly overlap, as best illustrated in Fig. 6, in order to get a good contact and also in order that the points may be kept bright or scoured and therefore free form corrosion, since corrosion would have a tendency to prevent good results for obvious reasons.

The two insulating blocks 15 and 1G are bored as shown at 23 and 24, approximately at right angles to the axes of the electrodes, in order to receive the forward extremities of the insulated conductors 25 and 26 which are inserted in said openings, the inner extremities of the conductors being connected with the electrodes as shown at 27 and 2S. The opposite extremities of these conductors are normally exposed as shown at 29 and 30, these exposed portions being adapted t-o connect with metal terminals 31 and 32, which contain sockets adapted to respectively receive the portions 29 and 30 of the said conductors. These terminals are connectedwith the opposite extremities 33 and 34 of the secondary wire of an induction coil 35 which is arranged in cooperative relation with a proper source of current as a battery 36.

The insulated conductors 25 and 2G and their corresponding insulated electrodes 17 and 1S, are first formed separately from the body of the tool as shown in Fi g. The handles 37 and 38 of the tool are preferably formed of sheet metal which is so stamped that when bent into proper form, these handle members are cylindrical or approximately cylindrical in shape and adapted to receive the conductors and 2G and the insulation 39 and 40 with which they are protected, as heretofore explained. The handles 37 and 38 are interiorly threaded at their rear extremities as shown at -11 and r-12 to receive insulating plugs 13 and 11 which are interiorly threaded as shown at 15 and 16 to receive the rear threaded ends of the insulation S9 and et() of the conductors. By virtue of these plugs the insulated conductors are spaced as shown at 17 and 18 from the met-al handles 37 and 3S. These handles areprovidedA at their forward extremities with metal extensions 19 and 50 which are channel-shaped to receive the extremities 8 and 9 and the insulating plugs 15 and 1G which constitute the jaws of the tool, the metal channel-shaped extensions 49 and 50 being secured to the jaws by means of suitable fastening devices as rivets 51 which are so disposed as not to interfere with the circuit of the device.

Vhen the tool is in use, both insulated conductors are connected in the circuit, both socket Aterminals 31 and 32 being applied to the corresponding exposed extremities 29 and 30 of the conductors. The jaws and handles of the tool are normally in the position shown in Fig. 2. rlhe fuse 52 to be acted on, is placed between the insulating blocks of the two jaws (see Fig. 2), then as the jaws arc closed by inward pressure on the handles, the fuse enters the recess 21 of the block 15 and the two cone-shaped points 19 and 2O of the electrodes enter the fuse from opposite sides and meet in the center where the powder is located. This meeting of the electrodes closes the electrical circuit. The operator then releases the pressure upon the handles of the tool and the recoil of the spring 1-1 instantly opens the aws and separates the points of the electrodes, whereby an electric arc is formed or produced which ignites the powder of the fuse. It is evident that the lighting of fuses by the use of my improved tool may be very quickly, easily and accurately accomplished. In other words, by reason of the construction of the tool as heretofore outlined, there is no opportunity for moisture to reach the powder as the fuse is pierced by the points of the electrodes. Consequently, the ignition of the powder will be instantaneous, due to the arcing of the current as the points of the electrodes are separated.

Having thus described my invention, what I claim is,-

l. A fuse lighter comprising two movable jaws hingedly connected adjacent one end, pointed electrodes carried by and movable with said jaws, said electrodes adapted to enter a fuse in opposing relation and engage each other to close an electrical circuit, means for normally retaining the jaws in position to separate the electrodes, and hanj dles secured to the respective jaws.

2. A fuse lighter comprising a pair of movable jaws hingedly connected near one end and at the opposite end terminating in a pair of handles, a pair of inwardly projecting cooperating pointed electrodes, one carried on each aw member, said electrodes adapted to contact each other in overlapping relation when the handles are operated to close the jaws and an electric circuit in which the electrodes are located.

3. A fuse lighter comprising a pair of movable jaws hingedly connected near one end and at the opposite end terminating in a pair of handles, a` pair of inwardly projecting coperating pointed electrodes one carried on each jaw member, said electrodes adapted to contact each other in overlapping relation when the handles are operated to close the jaws, and, spring means Jfor normally maintaining said jaws in open position with the electrodes out of Contact with each other.

A. A fuse lighter comprising two hinged members, pointed electrodes carried upon each member and each electrode projecting inwardly toward the opposite member, the two electrodes adapted to engage each other to close an electrical circuit.

In testimony whereof I aiiix my signature, in presence of two witnesses.

EDWIN C. WOOD.

Witnesses:

GRACE I-IUsToN, A. EBERT OBRIEN.

Copies of this patent may be obtained for ive cents each, by addressing the Commissioner of Eatents,

Washington, D. C. 

